Effects of cocaine and d-amphetamine on the repeated acquisition and performance of conditional discriminations.
Stimulants poison new learning faster than old habits, so ease stimulus-control demands when clients begin or change these meds.
01Research in Context
What this study did
Scientists gave pigeons a daily matching task. The birds had to peck the correct key when colors and positions changed.
Some days the birds got cocaine. Other days they got d-amphetamine. The team counted errors and pauses to see how the drugs hurt learning versus steady performance.
What they found
Both drugs made more errors and longer pauses. Learning tasks broke down at smaller doses than performance tasks.
After many drug days the birds needed bigger doses to get the same mess-up. This is called tolerance. Cocaine and speed also shared this tolerance, a sign of cross-tolerance.
How this fits with other research
WALLER et al. (1962) also gave pigeons d-amphetamine, but they looked at how the drug lifted suppressed pecking. Their birds pecked more, not less. The difference is the task: suppression reversal tests old habits, while repeated acquisition tests new learning.
Northup et al. (1991) used cocaine as a reinforcer and saw pigeons work harder for drug than food. Goldman et al. (1979) show the flip side: when the same drug is an antecedent, not a reinforcer, it wrecks new learning.
Haemmerlie (1983) split amphetamine’s motor and hedonic effects with curve fitting. The 1979 paper adds a third layer: stimulus-control demands make the drug extra toxic to learning.
Why it matters
If a client is on stimulant medication, start new skills at low mastery criteria. Keep the setting steady until the dose is stable. Watch for tolerance over weeks and raise criteria only when error rates drop without extra prompts.
Want CEUs on This Topic?
The ABA Clubhouse has 60+ free CEUs — live every Wednesday. Ethics, supervision & clinical topics.
Join Free →Cut the number of new targets in half for the first two weeks after any stimulant dose change.
02At a glance
03Original abstract
The acute and chronic effects of cocaine and d-amphetamine on food-reinforced behavior were investigated in pigeons responding on a two-component multiple schedule. In one component, the behavioral task consisted of the same chain of conditional discriminations each session (performance). In the other component, the chain of conditional discriminations was changed from session to session (learning). In comparison to control sessions, both acute cocaine and d-amphetamine increased errors in each component of the multiple schedule. Responding in the learning component, however, was generally disrupted at lower doses than those that affected responding in the performance component. At high doses, both drugs produced pauses in responding in each component in three of the four subjects. Pausing engendered by d-amphetamine was approximately twice as long as that under cocaine. Upon chronic administration, both the pausing and error-increasing effects of each drug diminished. Drug-induced changes in timeout responding, however, did not decrease during chronic administration. Redeterminations of the d-amphetamine dose-effect curves following chronic cocaine administration suggested the existence of cross-tolerance between cocaine and d-amphetamine. Both the acute and chronic data are consistent with the view that conditions of stimulus control may modulate the behavioral effects of drugs.
Journal of the experimental analysis of behavior, 1979 · doi:10.1901/jeab.1979.31-127